| 摘要 |
1465844 Cross-linked foamed olefine polymers FURUKAWA ELECTRIC CO Ltd 2 April 1974 [10 April 1973 29 May 1973 4 June 1973 30 Oct 1973] 14459/74 Heading C3C A foamed olefin polymer is made by (i) mixing 100 parts by weight of an olefin polymer with 0.01 to 3 parts by weight of a cross-linking agent which has a decomposition temperature higher than the ASTM D1525 softening point of the polymer, 0À1 to 30 parts by weight of a blowing agent which has a decomposition temperature higher than the decomposition temperature of the cross-linking agent and which evolves not more than 2 c.c. of gas per gram of blowing agent in 2 minutes after heating to 180‹ C. begins in the thermal decomposition test (as defined) and 0À01 to 2 parts by weight of a radical trapping agent which is a diallyl or triallyl ester of cyanuric acid, a diallyl or triallyl ester of isocyanuric acid, a polyallyl ester of a polycarboxylic acid, a compound containing at least two acryloyloxy radicals, a compound containing at least two methacryloyloxy radicals; a polymer having at least one double bond in each side chain, or triallyl phosphate, (ii) shaping the mixture, and (iii) heating it above the decomposition temperature of the blowing agent. In the examples low- or high-density polyethylene or an ethylene/vinyl acetate copolymer was mixed with azodicarbonamide, dinitrosopentamethylene tetramine or p-toluene sulphonyl semi-carbazide; dicumyl peroxide, 1,3-bis-(tbutyl peroxy-isopropyl)benzene or 2,5-dimethyl 2,5 - di - (t - butylperoxy) - hexyne - 3; and triallyl cyanurate, triallyl isocyanurate, trimethylolpropane trimethacrylate, 1,2-polybutadiene or triallyl trimellitate; the mixture was pressed or extruded into sheets, and the sheets were foamed by heating in an air thermostat, metal bath or in a wire-net conveyer in an oven. |
